The present invention is intended to provide a laser source for any wavelength, and of the type already known using erbium-doped fibers at 1550 nm.
Current in-line fiber optic amplifiers operate in the 1300 nm telecommunications window utilizing Neodymium (Nd)-doped gain media (both glasses and YAG). These devices provide single-pass gain to compensate for propagation losses incurred in optical fibers. A laser is the extension of single-pass amplification to multiple-pass oscillation by the addition of a cavity. In most conventional laser systems, the cavity is created using two or more mirrors. While a plethora of lasers have been developed using mirror cavities, extending these systems to fibers requires the use of costly and delicate fiber-coupling systems.
Some fiber laser systems have been developed in which a section of ion-doped fiber is spliced into a fiber ring, which acts as the cavity. Unfortunately, only a handful of doped glasses have been developed which can be fashioned into optical fibers, which provide only very sparse coverage of the entire optical spectrum.
What is required, are improved laser systems employing advanced optical amplification technology.
The present invention provides a compound waveguide architecture and associated amplification techniques to address this need, in both ring and linear cavity laser system configurations.